Torque measuring wrench



May 19, 1942.

File'd Nov. 22, 1937 6 Sheets-Sheet.

May 19 1942- H'. wz|MMERMAN 2,283,888

TORQUE MEASURING WRENCH Filed Nov. 22, 1957 e'sheets-sheet 4 H. w.ZIMMERMAN v TORQUE MEASURING WRENCH Flled Nov 22 1937 6 Sheets-Sheet 5nner/raz@ May 19, 1942-. H. w. ZIMMERMAN.

TORQUE MEAsUniNG wRENcn Filed Nov. 22, 1937 6 Sheets-.Shget 6 www @wwwSN Smm. N

Patented May 19., 1942 .UNITED STATES PATENT' `oI-Flc'zs l I. 'ronQUEMrisstsim WRENCH I M nafaziazsriergniwraae;

,Maintenance Machinery Co., North Chicago,

Ill., a corporation of Illinois Application November z2, 1931, serialNo. 115,863

Y (ci. zes-1) .I

38 Claims.

My invention relates to wrenches and it has to do more particularly withwrenches adapted for measuring the force or torque applied therethroughto nuts, bolts, studs, and other similar pieces of work.

My invention furtherhas .to do with a Wrench embodying relatively:movable members, such members being so .arranged that one of themisoperatively engaged with the work and relative movement between themembers is yield- Cil minimum percentage of error -as high' as 5 percent. Spring tension variation of this extent requires verycarefulhandling, sorting, testing and adjusting of springs that are to be usedin the manufacture of precision devicesrllke torqueV i. wrenches.

ably opposed by spring means. In wrenches of this character, the forc ortorque applied through the wrench is determined by measuring the extentof relative movement between the wrench members as permitted by'deflection of the opposing spring means.

The manufacture of a wrench of the foregoing kind presents .variousproblems, one of lwhich is inexpensive production of successive wrencheshaving a predetermined power rating and each of which will measuretheforce or torque applied to a certain piece of work in the same uniformprecision manner. `In other words, all

wrenches of a certain power rating produced for any particular kind ofwork should, preferably, measure the force or torque applied in asubstantially uniform manner without any appreciable variation inaccuracy. I have foundbe manufactured with each wrench adapted to thatthis conditionvpresents a dilcult problem. A

For example, coil springs have heretofore been employed for theforegoing purposes and, while they well serve their purpose in eachindividual wrench, they are subject'to certain conditions l involvingthe diiliculties abovev mentioned. As is well known, it is customary inthe manufacture of coil springs, and particularly those suitable fortorque measuring wrenches, to first form or. coil the spring fromrelatively soft wire and to then temper -the same to the desiredhardness -In this operation, a scale forms on the surface vofthe metalwhich cannot be prac- -tically removed in the formed coil spring, Vwiththe result that in a spring of this character, as

` it is compressed and expanded from time to time, the scale thereontends, to cause variation in accuracy of the tension of the spring. ThisOne of the objects of my invention is to pro- -vide an improved torquemeasuring wrench of the foregoing character which embodies spring meanswhich is not subject-to the foregoing obu .'Iectionable conditions andinwhich the diiiiculties mentioned are eliminated. l

Another object is to provide an improved wrench of the foregoingcharacter which is sim'- ple in construction, is inexpensive tomanufacture and to maintain in use, is of rugged vand compactvconstruction, and is adapted to measure the force ortorque .appliedtherethrough in a precision manner.

A further objectA isfgtp provide a torque measuring wrench of theforegoing character wherein relative movement between the relativelymovable wrench members is yieldably opposed by an elongated leaf-like.spring means,jwhich spring means is so constructed and arranged thatany number of successive wrenches of the same class and power embodyingthe same may uniformly measure, the force or torque applied to anyparticular piece of work.

An additional object is to provide an improved torque measuring wrenchof the foregoing character which includes a leaf spring member formed ofa high-grade steel to a predetermined size and shape and free fromscale, which spring is of such character that successive similar Vsprings may be made and' assembled yin the variation tendency indifferent springs. is not v uniform. These variable conditions existinglin dierentsprings necessarily cause variation in the tensioning actionof dierent coil springs even though they are manufactured successivelyundewthe same set of specications. For these ,n.wrearspns,l amongothersfmanufacturers of coil sprinsdo not usually guarantee the same tobe v overy long periods of time; and to provide anv accurately rated andthey usually allow for a 5.5

wrench with the assurance 'that successively made-wrenches embodying thesame will operate improved ratchet type torque measuring wrenchAembodying the foregoing features.

Other Objects andadvantages Awill become api' the use thereof.

parent as this description progresses and by reference to the drawingswherein- Figure 1 is a top plan view of one form of wrench embodying myinvention, the outer por-L tion of the handle portion thereof not beingshown;

Fig. 2 is a. vertical, -longitudinal sectional view taken substantiallyon line 2-2 of Fig. 1:

Fig. 3 is a top plan view of the structure shown in Figs. 1 and 2 withthe top cover portion thereof removed;

Fig. 4 is an enlarged section taken substantially online 4-4 of Fig. 2;

Fig. 5 is an enlarged section taken substantially on line 5--5 of Fig.3; Y

Fig. 6 is an enlarged side elevational view of the dial structure shownin Figs. 1 and 2;

Fig. 7 is a top plan view of another form of wrench embodying myinvention;

Fig. 8 is an enlarged horizontal sectional view of the wrench shown inFig. 7, which view is taken substantially on line 8-8 of Fig. 9;

Fig. 9 is a longitudinal, vertical sectional view taken substantially online 9-8 of Fig. 8;

Fig. 10 is a horizontal sectional view taken substantially on line 8 ofFig. 9;

s Fig. 11 is a fragmental sectional'view showing a modied form of meansfor mounting the spring which opposes relative movement between thewrenchmembers;

Fig. 12 is a view similar to Figs. 3 and 8, except showing a furtherVmodified form of wrench em,-

bodying my invention;

Fig. 13 is a longitudinal,- vertical sectional view taken substantiallyon line |3-I3 of Fig. 12;

Fig. 14 is a Vertical, longitudinal sectional view of still another formof wrench embodying my invention;

Fig. 15 is a horizontal sectional view taken substantially on line ||5of Fig. 14:

Fig. 16 is a section taken substantially on line except showing afurther modified form of wrench embodying my invention;

Fig. 20 is a longitudinal, vertical sectional view through the structureshown in Fig. 19;

Fig. 21 is'a fragmental view of a ratchet form of wrench embodying myinvention;

Fig. 22 is a section taken substantially on line 22-22 of Fig. 21; and

Fig. 23 is an elevational view, partially in section, illustrating meansthat may be applied to the wrenches shown in Figs. .2 and 21 forengaging the wrench with the work and also for aiding in support of thewrench upon the work during.

I'he wrench shown in Figs. l to 6, inclusive, includes a chambered head30 to which is connected a handle 3|. The head 30 includes a bodysection 32 having a rather deep chamber 3|)a therein and a top coversection 33 vsecured to the body'secti'on 32 by a plurality of screws orother fastening devices 34.

The forward end of the head 38 rockably supports a work-engaging member.More particularly, the body and cover sections are provided with alignedopenings 38 and 31 in which are received upper and lower reducedcylindrical hub-like portions 38 and 38 on the annular head tween thesleeves 54, 55 in which the rear end Y .of the spring 44 is received.

253 of the work-engaging member. The work- 75 engaging member isprovided with a central opening 40 of rectangular or other suitableshape to prevent rotation of the supported part, and this opening isadapted to receive any suitable work-engaging adapter (not, shown) foroperatively connecting the wrench with the work.

The work-engaging member 35 is further and operably connected withY thetool head 30 (Figs. 2 and, 3) by spring means in such a. way thatrelative rock movement between the head and.`

attachment head portion 42 (Figs. 2 and 3) having a longitudinallyextending and vertically disposed slot 43 therein. The spring means thatI employ takes the form of an elongated leaf-like spring member 44having its forward end received within the arm slot 43 and iixedlysecured thereinqby rivets 45 or other suitable securing devices. It isto be understood that the spring member 44 may be referred to as a stripspring member and that it may take the cross-sectional shape shown orany other suitable cross-sectional shape such as square, circular, ovalor the like. The rear end of the spring 44 is connected to the wrenchhead 38 by a support unit 41 (Figs. 2, 3 and 4) which is automaticallyadjustable as the spring 44 is deflected to compensate for the changedposition of the deflected spring and thereby avoid abnormal distortionof the spring, which, if it should occur, might create a conditioncausing a `:i'alse registrationV of the torque or force being applied tothe work.

The support unit 41 is located at the rear end of the wrench headchamber 3l)a and it is pivotally carried by these sections in such a wayas to maintain at all times substantially the same alignment relationbetween the longitudinal center line of the spring 44 and the axis oithe unit 41. Speciiically, the unit 41 (Fig. 4) includes a pair of endplate members 48 and 49 each having an outwardly extending cylindricalstud 50 rotatably engaging, respectively, in openings 5| formed in thebody and cover sections 32 and 33. 'Ihe end plates 48, 49 are connectedtogether in spaced relation by post members 52 and 53 around which aredisposed roller sleeve members 54 and 55. The post members 52 and 53 arespaced apart to such an extent and the sleeves 54 and 55 are of suchdiameter as to provide a space 56 be- It will be seen that in the use ofthe foregoing structure, with the work-engaging member 35 applied to thework and with the operator grasp-4 ing the handle 3| and moving the sameto tighten or loosen the work, the handle 3|, the tool head 30, thework-engaging member 35 and the work will tend to move as a single unit.However. when the work offers ,suiilcient resistance to turningmovement, as when tightening the same, to overcome the initial tensionof the spring 44, such spring will be deiiected, permitting relativerock movement between the work-engagingmember 35 and the tool head 30.As the work offers added resistance, the deection of the spring 44 willbe increased, during which time the spring 44 becomes slightly bowed. Asthe spring 44 is de iiected and bowed, the spring connecting unit 41will rotate in its bearings 50 to accommodate the vchanged angularposition of the spring 44 caused by its'bowing so that the end portionof the spring 44 engaged with the unit 41 will always assumesubstantially the same position relative to the axes of the rollers 54,55 of the unit 41, avoiding any cramping of the deiiecting spring thatwould tertild to influence or upset its normal deflecting ac on.

In further carrying out my invention, I con` struct the strip springmember 44 in such a way as to insure its operation wtih a high `degreeof accuracy at all times. The construction of the spring member is suchthat, for any particular wrench having a particular rated power, anydesired number of springs may be made up and, when applied to wrenches,they will all function with substantially uniform rated accuracy. Tothis end. Ivemploy a spring member formed of a high-grade steel which istempered to the desired hardness to provide the desired tension rating.The tempered spring is then ground or otherwise treated to remove allscale therefrom and to give it predetermined dimensional characteristicsso that aV predetermined pressure will be required to cause an initialdeflection of the spring and to cause deflection of predeterminedextent. By providing a strip spring member of this character I iind thatby mounting it in the manner described, the force or torque applied tothe work may be measured in aprecision manner and that manufacture ofwrenches of this character in quantity is facilitated and may be carriedout inan inexpensive way without sacriiice in precision requirements.For any particular wrenches of predetermined size and power rating,parts may be made up in quantity with the assurance that they may beassembled into com; plete wrenches that will have the desired powerrating. y

It will be understood that the power rating of any spring 44 may bevaried by changing the cross-sectional area thereof and/or by using aspring having a greater or less active length beduced with eachhaving 'asubstantially uniform power rating.

' The relative movement between the head 30 and the work-engaging member35 is measured,

preferably (but not necessarily) in terms of inchpounds pressureapplied, by indicating mechanism which will now be described.Specifically, I employ a detachable indicator unit which includes acup-shaped casing 51 (Figs. 1 and 2) having its bottom part secured vtothe cover section 33 by a pair of diametrically opposed screws 58. Theopenings through which the screws 56 Iextend take the form of elongatedarcuate slots 59 that'permit substantial rotation of casing 51,- whichrotation is tensioned by spring washers 60 disposed between the heads ofthe screws 58 and the adjacent wall of the Vcasing 51. The casing 51 isprovided 'with' an inverted, cup-shaped, transparent cover 6|, having askirt portion 6| snugly fitting against the inner part of the side wallof the casing 51. The side wall of the casing 51 is provided vwith acircumferentially ex' tending slot 62 (Fig. 6) which is covered by thetransparent cover side wall 6|,` for a purpose which will be referred tomore particularly hereinafter.

The indicator unit further includes an inverted cup-shaped dial drum 63(Fig. 2), the'side wall i 'I'he top of the transparent cover 6| has anindicating mark 66 and the skirtA 6|a of the transparent cover at thecenter of casing slot 62 is providedA with a corresponding indicatingmark 61. With the foregoing construction, the casing 51 and cover 6| maybe set as a unit so that the indicating marks 56 and 61 coincide'Withany desired mark (zero, for example) on the dial scales 64 and 65,respectively; and, by rotating the dial 6| in either direction, theextent of relative movement of head 30 and member 35 and the pressureapplied through these members to the work will be indicated by theextent of movement of the dial scales relative to the indicating marks66 and v61. 1

The dial drum 63 is carried by a tubular shaft element 68`which extendsdownwardly through the central Vboss-.like portion of the bottom part ofthe casing'51 and it xedly receives a shaft 69 extending into .the headchamber 3|]a where it receives a pinion 10 which is operatively engagedwith a rack' member 1| carried by the work-A engaging member arm 6|., y

'I'he rack member 1| is provided with a squared and toothed rack portion1|a which directly ensupporting arm 4| when relative rock movementVtakes place between the head 3l) and work-engaging member 35.Specifically, the rack mem'- ber is of T-shape and its T-stem portion1|h is snugly andslidably received in a slideway 12 formed by a recessin a cross plate 13 supported by the upper rear end portion of thework-engaging member arm 4|. The rear end of the rack member stem 1|b isengaged by a U-shapen spring 14 carried by the arm 4|, which spring isso constructed and arranged as to continuously urge the rack member`forwardly into engagement with the pinion 10 'but will permit the rackvmember to be movedvbackwardly and forwardly to accommodate the arcuatemovement of the rack member above vmentioned. With this.

arrangement, as soon as the work oiers sufcient resistance to overcomethe initial-tension of the spring 44, such spring will be deected andthe head member 30 will rock relatively to the workengaging member 35and itsarm 4|, therebylmoving theindicating unit' 51 and its pinion 1Brelative to-the rack member 1| and causing the dial drum 63'to rotate.The extent of rotation oi' the dial drum and the amount of pressureappliedto effect such r'btation may be accurately determined by notingthe extent ofmovement of the dial scales relative to the indicatingmarks 66; and 61. At times, the operator, when actuating' i the wrench,may be' in such aL position that the dial scale 64 is within his visionWhile, at other times, the dial scale '65, at the side ofythe dial drum,may be within his vision. In either event,

, length are provided on opposite side walls of the head chamber 30ELadjacent the rear end of the arm 4|. The forward end of the arm 44| willabut against the stops 32 and 32b upon a predetermined, relativerotational movement between the head 30 and work-engaging member 35.These lugs 32a and 32b are of such length that they stop furtherrelative rotational movement of the parts when the safe deflection limitof the spring is reached or is nearly reached. Of course, the stop lugs32 and 32b maybe of any desired length to limit the deection of thespring 44 to any desired extent.

Wrenches embodying my invention may take various forms, and in Figs. 'Ito 10. inclusive, I have shown another form which may well serve mypurpose in taking care of certain kinds of work. Specifically, thiswrench includes a head 80 having a handle 8| thereon. The head 80includes a bottom chamber section 82 and a removable top cover section83 which supports an indicating unit' 84. The head'sections provide ahead chamber 85 in which I rockably mount a workengaging member 86. Thework-engaging member is provided with a stepped stub shaft portion 81which iinds suitable bearing in a thickened forward portion or boss 88in the bottom section 82, and this shaft is of sulcient length to extendbelow the boss 88 where it receives a collar 89 secured thereto by lockscrews 90, whereby the shaft and the work-engaging element 80 areiixedly secured in place for rock movement. The outward projecting endof the shaft 81 is provided with a shank or other suitable means 9| fordirect engagement with the work or for reception of suitable adaptermeans which may be engaged with the work, as determined by the characterof the work to be tightened or loosened.

The work-engaging member is slotted to receive one end of a strip springmember 92 similar to the previously described spring 44 and which springis secured in place by screw members 93. The spring 92 extendsrearwardly within the head chamber 85 and its rear end is operablyconnected with the head 80 by adjustable abutment means. Moreparticularly, the head 80 near the rear end of the chamber 85 iseprovided in its sides with aligned threaded openings 9| in which arereceived abutment members having a threaded shank 95 and a roundedabutment head 96 projecting into the head cham-4 ber. The spring 92extends rearwardly between the abutment members and such members areadjusted inwardly, preferably to similar extents, substantially intoengagement with the side faces of the spring 92 so that when the wrenchhandle 9| is grasped and rotated in either direction the pressureapplied will be transmitted through the head 80, the spring 92 and thework-engaging member 86 to the work.

As in the first-described form, when the work oil'ers sufficientresistance to overcome the initial tension of spring 92, relative rockmovement takes place between the head 80 and work-engaging member 86,and by measuring the extent of Vvthis movement one may determine,through the message plied. The indicating unit 84 may include a hand 91movable relative to a dial 98 having a scale 99 thereon calibrated toregister, preferably (but not necessarily), inch-pounds pressure. Thehand 91 is connected through suitable shaft means |00 to a pinion |0|which is operably lconnected to the work-engaging member 8S.

More particularly, the work-engaging member 06 is connected to thepinion |0| by an arm |02, the forward end of which is fixedly secured tothe work-engaging members by screws or otherl suitable fastening devices|03. The rear end of the arm |02 is provided with a rack portion |01mwhich engages the pinion |0|; and, with this arrangement, when the workoffers sufficient resistance to cause deflection of the spring 92 andrelative movement of the head 80, as when tightening the work, suchmovement of the head and pinion |0| relative to the 4rack portion |02*will cause the gage hand 91 to rotate relative to the dial scale andregister theextent of this movement in terms of pressure applied.

'Ihe side walls of the bottom section 82 of the head are provided withstop lugs |04 which are adapted to engage the vopposite faces of thespring 92 upon a predetermined relative rotational movement between theparts, thereby limiting the extent of deection of the spring 92 withinsafe operating limits. This arrangement is substantially the same as thespring stop arrangement of the rst-descrlbed form, except that the stopmembers here engage the spring `chamber 85, and the rear portion of thewall of this chamber is provided with a pair of vertical andarcuate-shaped roller seats |08 in which the rollers |05 are received.These rollers are of such diameter and the seats |09 are spaced apart tosuch an extent that the rear end of the strip spring |09 is snuglyreceived therebetween. The roller action between the spring and rollerswill tend to minimize the tendency to cramp the spring |09 andabnormally distort the same.

My invention is also adaptable to so-callcd double-handle wrenches, orwrenches having two oppositely extending handles adapted to be graspedbythe' hands of a single operator or by different operators. To thisend, I may employ a structure similar to that shown in Figs. 12 and 13,which includes a wrench head ||0 having aligned handles and ||2extending from the opposite ends thereof.

The wrench head ||0 (Figs. 12 and 13) is formed of a chambered bottomsection ||3 and a top section ||4 providing a head chamber ||5.`

Within the chamber ||5, and preferably midway between the handles ||2, Iemploy a workengaging member ||6 similar in construction and mounting tothe work-engaging member 8S of the second-described form. Thework-engag-y ing member A| I6 is provided with a cross slot in which issecured a strip spring ||1. vThe spring ||1 is of suicient length toextend substantially throughout the length of the head chamber ||5 andits mid-portion is secured in the workengaging member slot by suitablerivets or other indicating unit 84, the amount of pressure apfasteningdevices ||8. In this way, strip spring arms or elements ||`|a and H11.of substantially equal length,'extend in opposite directions from thework-engaging member H6. If desired, the -strip spring arms may take theform of separate spring members having their Aadjacent ends rigidlycarried by the work-engaging member I Iii.`

The free ends of the spring arms ||1a and ||`|b are operably connectedwith the head by rounded abutment elements ||9 and |20 disposed on theopposite side walls of the head so thatr when the handles and ||2 aregrasped and rotated in clockwise direction (as viewed in Fig. 12), as intightening the' work, both spring arms ||`|a and I1h will be effectiveto yieldably oppose relative rotation between the head I |0 andworkengaging member IIB. Y

In the use of this structure, as with the previ-d, ously describedstructures, when the work offers i suilicient resistance to overcome theinitial tension of the spring arms I |1a and lll", head ||0 will rotateclockwise relative to the work-engaging member and, by measuring theextent of this movement, one may determine the amount of pressure.applied. This measurment may be accomplished by an indicating unit |2|similar to the indicating unit of the rst-described form,

rexcept that a stationary dial |22 and a rotatable hand |23 are employedinstead of the drum dial structure 63.

The rotatable hand |23 (Fig. 13) which corresponds to the hand 91 (Fig.J7) is carried by a rodeectfthe same. This feature may serve-forcompensating purposes, as, for example, slight wear of the parts maytake place over a long period of use and the gage mechanism'may for thisreason fail to register accurately., By setting up the screws. |33 and|34, any out-of-register condition, and particularly an initial registercondition, maybe corrected. So far as the loosening action isAconcerned, it will be seen that when the wrench handles are moved in acounterclock.-A

wise direction, the head ||0 and screws |33, |34

contact the spring arms H1, ||1b in close proximity to the work-engagingmember IIB so that the loosening pressure may be applied through asubstantially rigid series of connections. will be understood that, sofar as the foregoing tensioning feature is concerned, it may well beapplied to any of the wrench forms disclosed herein.

In certain instances it may be desirable to employ wrenches having longhandles, and where tatable shaft |24 which extends into the `headchamber ||5 where it receives a pinion |24. The -pinion |24 meshes witha larger gear |25 supported by a shaft |26, the opposite ends of whichare journaled in the cover section ||4 and in a cross-supporting bracket|21 secured to the under side of the section ||4 by screws |28. -Theshaft |26 carries another small gear |29 which meshes with a largergearl|30 having'a hub portion |3| detachablyvsecured to the upperportion of the work-engaging member by a pair of spaced pins |32 (onlyone shown in Fig. 13). With this arrangement, as relative rotationalmovement takes place between the head ||0 and the work-engaging memberH6, the movement of the gear |29 relative to the gear |30 transmitsmotion to the hand |23 through the gears |25 and |24. The.

dial |22 is provided with a'scale (not shown) similar to the scale 99(Fig. 7) calibrated, preferably, in terms of inch-pounds pressure, andby reading the extent of monvement of the hand |23 relative to the dialscale, the operator may determine the amount of pressure applied.

'I'he wrench structure shown in Fig. 12 is adapted particularly formeasuring the pressure applied in tightening the work. To adapt thewrench for operation as a substantially rigid structure when looseningthe work, I provide ad- 'J'ustable abutment screws |33 and |34 in theopthe work acted upon is at a considerable distance away from theoperator so that he cannot readily observe the indicating mechanism whenit is located as shown in the previous forms. To take care of thiscondition, in the use of my invention,

, I may employ the structurei'shown in Figs. 14 to 16, inclusive. 'Ihisstructureincludes a head |40 and arrqelongated hollow handle |4'|.` Thehead |40, the work-engaging member |42 and strip spring |43 of this formare substantially identical with the form of Fig'. 8 and it will not,therefore,

Abe necessary to describe these parts and their mountings in detail.

Relative rock movement between the head |40 and work-engaging member |42is measured by an indicating unit |44 which is substantially the same asthe indicating units of the forms of Figs.

`8 and 13, except that this unit is located remotelyfrom thework-engaging member |42 and in close proximity to a handle portion |45that may be grasped by the operator. The unit |44 is prov 4vided Withatubularbody portion |46 which receives the rear end of the forwardhandle portion |4| and the forward end of the rear handle portion |45,thereby coupling these-handle portions together as a unit.

Relative rock movement ofthe parts is transmitted to the indicating unit|44 by transmission mechanism which will now be described. Thistransmission mechanism includes a ilat arm |41 mounted within the head|40 and a shaft |48 posite side walls of tlfe bottom head section ||3,

which screws are opposed to the abutment elements ||9 and |20. Thescrews |33 and |34 may be adjusted into light engagement with the springarms ||1a and I1", respectively, or they may be slightly spacedtherefrom, as desired. In either event, they are locked in the desiredposition by the lock screws |35 and |36. The screws |33 andv|34 mayserve, when adjusted into contact with the spring arms H1, Ill", as

connected to an indicator pinion |49 by a` gear |50. The forward end ofthe arm |41 is xedly secured to the work-engaging member |42 by screwsor otherv suitable fastening devices |5|. This arm extends rearwardly`slightly past the rear end of the spring |43 and it is provided with alongitudinally extending elongated slot |52 in which isreceived anupstanding arm |53 on a head member |54 secured to the forwardlyextending end of mesma ,14s. The shaft is ro tatably supported bysuitable bearing members initial tension adjustment means. It will beseen that by setting up -these screws' against the spring arms to any,desired extent, the initial tension of the spring arms may be increasedso that a greater initial pressure will be required to the parts arereturned to normal position, thel reverse movement of the parts takesplace. Backlash in both of these movements is guarded against by aclock-type spring |59 (Fig. 16) having one end secured by a screw`|59 tothe bottom section of the wrench head, the same extending spirallyaround the shaft head |54 and being connected to such head as at |60.This spring tensions the movement of the shaft in such a way ashto causeit to move with a smooth action, thereby insuring a more positive andaccurate Vindication by the indicating unit.

In certain instances, I may employ a pair of separate, independentlyacting strip spring members for measuring the pressure applied in bothtightening and loosening the work. Such an arrangement is shown in Figs.l'land 18. Referring particularly to Fig. 17, the structure shown issimilar to that of Figs. 1 and 2 except that the rear end ofthework-engaging member arm |19 is shaped to. provide a reduced tongue towhich the forwardly extending ends of similar strip spring members |1|and |12 are secured in oppositely facing relation by rivets or othersuitable fastening devices |13. 'I'he rear end portion of the headchamber |14 is provided with an upright post member |15 around which isdisposed a sleeve unit |19 that provides a roller abutment mounting forthe rear ends of the spring members |1| and |12. That is to say, thespring members |1| and |12 are long enough to extend rearwardly slightlypast the roller unit |16, andgrip portieri la: which facilitates use'ofthestructure.

Relative-rotation or rock movement between the head |80 and handle |85is'yieldingly Icpposed by a strip spring member |98` carried` by thehead |80. To vthis end, Spring Supporting* block members |94 and |85 aremounted within and adjacent the opposite ends of the head cham- |93 onthe opposite sides thereof. In this way,

the tendency of the handle |85 to rotate relatively to the head isvyieldingly opposed by the spring |93 but, when the work offerssufllcient resistance to overcome the initial tension of such spring,

'the spring will be deflected and deflection will' take place to anextent dependent upon the amount of pressure applied. f Y

By measuring the extent of this deflection, I determine the amount ofpressure, preferably -inch-pounds, applied through the handle and catingstructure may include a rack member |18 engaged with a pinion |19adapted to be carried by an indicating unit connected to an indicator ofany suitable kind as, for example, the drum dial 53 of Fig. 2 or thegage hand 91 of Fig. 7.

My invention is also well adapted to an arrangement'wherein the wrenchhead portion is adapted to be non-rotatably secured to the work, and thehandle part which the operator grasps is, on the other hand. rotatablerelative to the work. In Figs. 19 and 20 I show a wrench of thischaracter which includes a chambered head |80 having, on the lower sideof its forward end,

a thickened boss portion |8| to the bottom of which is detachablysecured, by screws or other fastening devices |82, a work-engagingadapter member |83.l Within the chamber |84 ofthe head I rotatably orrockably mount a handle I member |85. More particularly, the forward endprojecting end of the handle is provided with a.

spring to the work. The mechanism for measuring this deiiection may takethe form of indi-l eating mechanism like that shown in Fig. 3, in-

cluding a pinion 280 supported by a head-carried gage device 28| and ayieldable, shiftable rack member 282 carried by the handle |85. Otherthan above stated, the operation of this form of wrench is substantiallythe same as the forms previously described.

In taking care of various kinds of work. it is desirable to employ aratchet form of wrench structure. My invention is well adaptedvto awrench of that character, by so constructing the ratchet mechanism thatwear thereof is minimized and any distortion thereof which would causeinaccurate reading of the gage structure is avoided. In Figs. 21 and 22,I have shown one form of torque measuring ratchet -wrench in which theforegoing objectionable conditions are avoided, and which is adapted tooperate with a ratchet action while, at the same time, measuring theforce or torque applied in ahighly efllcientand accurate manner. Moreparticularly, referring to Figs. 21 and 22, I employ a head part 2|0which may be similar .to thel heads of the wrenches shown in,Figs. 1 to18, inclusive. and which is provided at its .rear with a handle (notshown) adapted to be grasped by the operator. Within the wrench headchamber 2|| I rotatably mount a work-engaging member 2|2 with which isassociated ratchet mechanism. More particularly, thebody and coverportions 2N* and 2||lb of the wrench body, at the forward end thereof,are provided with aligned openings 2|8, 2| 4 in which the oppositereduced end portions of the work-engaging member 2|2 are rotatablyreceived. For friction-reducing purposes, the opposite ends o! thework-engaging member 2|2 are engaged with the body by anti-frictionbearing members 2|5 and 2li. Upon the central and enlarged portion ofthe work-engaging member 2|2 I rotatably mount an arm 2I1 `which may beconstructed similarly to the arm shown in Figs. 2 and 3. The rearcreases member 2| 2 are operatively connected as a rigid work-engagingmember 212 by a ratchet mechanism which will now be described.

lSimilar ratchet wheels '2I8 and 219 are mounted upon the reduced endportions of the work-engaging member at the opposite ends of unit whenvthe wrench is moved in a' clockwise direction (as viewed in Fig. 21) totighten the work. When the wrench is moved in the opposite direction,with the parts so set, the ratchet wheels 2I8 and 219 will remainstationary and the pawl elements 226, through the yielding connection'aiorded by the springs 221, will slip in counterclockwise direction overthe teeth of the enlarged central portion of such member. i

The ratchet wheels each have a .polygonally shaped central opening andthe portion of the work-engaging member engaged thereby Amay becomplementally shaped so that the ratchet wheels are non-rotatably xedupon the workeng'aging member v 2I2. The arrangement of these parts issuch that when the bodyl cover, the work-engaging member, arm 2|1 andratchet wheels are assembled in themanner shown in Fig. 22 and they aresecured-in that position by one or more cover screws 220, the parts areoperatively assembled so that the ratchet wheels rotate with thework-engaging member.

The ratchet mechanism further includes a pair of double pawl members221, 22.2 carried by the arm 2|1, which serve to operatively onnect sucharm with the work-engaging member. More' particularly, a shaft 223 isrotatably mounted in the arm 2|1 and has reduced end f portions 223a and223b projecting above and below such arm. Upon-the reduced end portions223a and 223b ofthe shaft 223, -and in guide-abutment engagement withthe upper and lower sidesof the arm 211, I flxedly secure the pawlmembers 22| and 222.

ject forwardly so that in certain adjusted positions thereof they will,respectively, engage the teeth of the ratchet wheels 218 and 219. Thepawl members 22|, 222 are moved simultaneously to similar extents byadjustment of the shaft 223 and when these members are rotated to theposition shown in Fig. 1, the pawl element 226b is thrown intoengagement with the r tchet wheels. The pawl members are held in thposition shown by' the upper and lower laterally directed leafl springmembers 221 which have V-shaped mid portions that are engaged bysimilarly-shaped projections 228 on the adjacent peripheral surfaces ofthe pawl members. `Such spring members yieldably hold the pawl The end223a of the shaft 223 extends upwardly and through anv of the ball-likehand-grip member 231.

members in'the position, for example, shown in Fig. j21; however, if `itis desired to reverse the pawl action so that the pawl elements 226 areoperatively Vengaged with the ratchet wheels,l it is only necessary tograsp the finger-piece 225 and rotate the same in counterclockwisedirecticn (as viewed in Fig. 21) to snap the pawl member projections 228on the side of the V-shaped spring portions opposite that shown .in Fig.21.

. In thev use ofthe ratchet structure shown,

" with the pawl element 221ib engaged withthe the ratchet wheels. Inthis way, an ordinary ratchet action is accomplished in tightening or4moving the work in a clockwise direction. The

same operation takes place when the ratchet members 22|, 222 areadjusted, as above stated, to operatively engage the pawl elements 226e.

be connected to the Work through a work-adapter member such as themember 230 shown in Fig. 23. To this end, the work-engaging member 23|is provided with a rectangular, or other noncircular opening, and theupper or inner end of the work-adapter member 2,30 is vsimilarlyshaped.4 Thispart of the member 230 may be provided with a spring andball friction attachment 232 to prevent the adapter member fromaccidentally becoming detached. Such adapter may also be provided withstop lips or lugs 233 for preventing the adapterfrom being inserted toofar within the work-engaging member opening. The lower projectingportion of the workadapter member `230 may also be provided with aspring and ball attachment connection 234 so that a socket ork otherwork-engaging element may be firmly held in place thereon.

At times,'the operator may wish to rest his A hand upon the forward partof the Wrench .to

steady his movements in tightening the Work.

In that case, I may employ the hand-supporting structure shown in Fig.23. Specifically, the upper end of the work-engaging member openingreceives a hand supporting unit having a shank portion 235 constructedsimilarly to the upper or inward end of the work-adapter member 230. Theshank portion 235 projects outwardly above the wrenchv structure as at236 and is, preferably, of -cylindrical shape for rotatable receptionThe cylindrical extension 236, inwardly from the end thereof, isprovided with a groove 238 for the reception of a stud 2394 carried bythe grip member 231, whereby the grip member is rotatably fixed againstoutward displacement upon the cylindrical extension 236. The extent ofinsertion of the shank 235 within the work-engaging member opening islimited by stop lugs or the like 240 similar to the stop lugs 233.

I believe that the operation and advantages of my invention as abovefirst stated will be readily understood from the vforegoing description.It is to be further understood that while I have shown and describedseveral forms of wrenches embodying my invention, other changes indetails and arrangements of parts'may be resorted to with out departingfrom the spirit and scope of my invention as defined by the claims thatfollow. For example, in a two-spring construction like that shown inFigs. 17 and 18, the springs may be xedly carried in laterally spacedrelation by the wrench head and their free ends may frictionally andfreely engage the opposite sides of the end Aspring is fixedly connectedat one end to the head `instead of to the work-engaging member arm.

I claim: l. A torque measuring wrench comprising a head member having achamber therein, a workengaging member rockably mounted in said chamberand having an. exposed part adapted for extent of relative rock movementof said head and work-engaging members.

6. A torque measuring wrench comprising a head member, a work-engagingmember rockabiy supported thereby, a strip spring member,

- means for connecting one end of said spring engagement with the work,a normally straight and stiff strip spring member mounted in saidchamber and having one end connected to said work-engaging member, meansmounted in said chamber having slidable engagement with opposite sideportions of said spring member and connecting the other end of saidspring member with said head member so that right and left hand threadedwork may be tightened, pressure indicating means, and means between saidindicating means and said work-engaging member for actuating the formeras said head and workengaging members rock relatively.

head member, a work-engaging member rock` ably supported thereby, astrip spring member, means for rigidly connecting one end of said springmember to said work-engaging member, a roller support for the other endof said spring member having a swivel connection with said head memberto accommodate ilexing action of said spring member as said head andwork-engaging members are rocked relatively, and means for indicatingthe pressure applied to the work through said members.

4. A torque measuring wrench adapted for use with means for indicatingthe force applied by the wrench to the work comprising a head member, awork-engaging member rockably supported thereby, a strip spring member,means for connecting one end oi' saidl strip member to saidwork-engaging member, and abutment connection means between the otherend of said spring member and said head member, including a pair ofrollers between which said other end of said spring member is received,means supporting said roller members as a unit and for rotativelyconnecting such unit to said head member.

5. A torque measuring wrench comprising 'a head member, a work-engagingmember rockably supported thereby, a strip spring member, means forconnecting one end oi said spring member to said work-engaging member, apivotal support for the other end of said spring member carried by saidhead member; said support contlnlng said end ot said spring memberagainst member to said work-engaging member, an abutment roller supportfor the other end of said spring member, comprising a-pair of spacedroller members carried by said head member and between which theadjacent end of said spring member is freely received, and means forindicating pressure applied to the work by registering extent ofrelative rock movement of said head and work-engaging members.-

7. A torque,measuring wrench comprising a head member having a chambertherein, a workengaging member rockably mounted in one end of saidchamber and having an arm` extending rearwardly toward the other end ofsaid chamber, the rock axis of said work-engaging member :oincidingwiththe axis of rotation of the work, a normally straight spring bar rigidlyconnected at one end to and extending lineally from the rear end of saidarm and connected at its other ably connected thereto, a long normallystraight spring bar connected at one end yto said workengaging member,means engaging opposite sides of said spring bar and connecting itsother end to said'head member, whereby said spring bar yieldably opposesrelative rock movement of said members in opposite directions, stopmeans for limiting the extent of relative rock movement between saidhead and work-engaging members i and also the extent of deiiection ofsaid spring bar, and indicating means for registering the extent of saidrelative rock movement.

9. A wrench for applying torque in opposite directions comprising ahea'd member, a workengaging member rockably connected thereto, a longand normally straight spring bar, means rigidly connecting one end ofsaid spring bar to one of said members, adjustable abutment meanscarried by the other of said members and en-f gaging opposite sideportions of said spring bar and operatively connecting said spring barwith said other member, and indicating means for registering the extentof relative rock movement between said head and work-engaging members ineither direction.

10. A torque measuring wrench comprising .a head member having provision:or operably engaging it with the work, a handle member rockablyconnected to said head member, a strip spring member carried by saidhead member in such a mannerthat its'mid portion is free to ilex, andmeans operably connecting said handle member to said midportion so thatsaid spring member yieldably opposes relative rock movement between saidhead and handle members.

11. A torque measuring wrench comprising a hollow head member having anelongated slot in its rear wall and also having provision for operablyengaging it with the work. a handle i members.

' work engaging member having meansthrough Y provide a substantiallyconstant moment arm,

escasas v member, said spring bar having one 'end conmember projectingthrough said slot into said head member, means in said head membervwhereby said handle member is rockably connected to saidhead member, astrip spring membercarried within said head member in such a manner thatits midportion is free to flex, means within said head member operablyconnecting said handle member to said midportion so that .said springmember yieldably opposes-relative rock movement between said head andhandle memberaand means indicating extent of relative rock movement ofsaidhead and handle 12. A torque measuring wrench adapted for I to thework which comprises, a handle member having a grip portion adjacent oneend thereof, 'a work-engaging member pivotally connected with the otherend'of said handle member, said whichit may be connected with the work,which nmeans is located substantially on the pivotal axis whereby when arotary force is applied to said grip member the same will be transmittedthrough said handle member to said4 spring bar and through said springbar to said work-engaging. member. i

13. A torque measuring wrench adapted for use with means forindicatingthe force applied to the work, which comprises a handle memberhaving a grip portion on one end thereof, a workengaging member havinglm elenient thereon which is adapted to be the work, said work-engagingmember having -aportion pivotally connected to the other end of said'handle member, substantially on the-axis of said work-engaging element,a spring bar supported by one of said members in end to end alignment'with said pivotally connected portion yand said grip portion, whichsaid spring bar is held 'against longitudinal displacement relative tosaid' one member, a connection between the other of said members andsaid spring bar. said connecj tion permitting slight longitudinaldisplacement of said spring bar, whereby relative rotation ef tween said-members causes deflection of spring bar :nid there is prdvided aconstant moment arm through which force is applied from said gripportion through said handle member,

'thence through said spring bar, and finally through said work-engagingmember to the work.

14. A torque measuring wrench adapted for use with means for indicatingthe force 'applied to the work:v which comprises, a handlemember alongitudinally extending grip portion "adjacent one end thereof. a workengagingfmemt0 `Iid grip portion' and work engaging- 75 nected to saidwork engaging member with its other end slidably connected with saidhandle' -member at a point radially inwardly of said grip 4 portion.whereby there is provided a constant moment arm andv pressure applied tosaid grip 15. A torque measuring wrench adapted for use with means forindicating the force applied to the work whichcomprises, a handle memberhaving a longitudinally extending grip- Portion adjacent one -endthereof, a work engaging member pivotally supported adjacent the otherend of said handle, the pivotal axis of said work-engaging membercoinciding with the axis of rotation of the work, a normally straightspring bar disposed in radially aligned end to end relation to saidgrip" portion and said work engaging member, said spring bar having oneend thereof ilxably connected to one of said members and its other end-engaged with the other of said members, whereby there is providedaconstant moment arm and pressure applied to said grip p0rtion istransmitted to thework through said handle member, -thence forwardlythrough said spring bar and iinally through said work engag y ingmember. t

16. A torque measuring wrench which comprises ahandle member, awork-engaging member pivotally supported adjacent one end ofsaid handlemember, the pivotal axis of said workengaging mem-ber coinciding withthe axis of ro tation of the work, an arm on said work-engag-l ingmember and extending `longitudinally of said handle member, a springbarhaving one end carried by said armand extending longitudinally alongsaid handle member, said arm and spring .bar constituting a continuousmoment arm of substantially constant length, means for connectingthevother end of said spring Abar with said handle member, means forregistering deilection of said spring bar to indicate force applied tothe work including relatively movable elements, and means carried by,said moment arm and adapted to cooperate with one of said relativelymovable elements of saidl indicatingV means to operate the latter.

17. A torquev measuring wrench which comprises, a handle member having agrip portion, a work-engaging member pivotallysupported adjacent one endoi' said handle, the pivotal axis of said work-,engaging membercoinciding with the l axis of rotation of the work, an arm member onsaid work-engaging member and extending longitudinally of said handlemember, a spring bar extending from s aid arm longitudinally of saidhandle member and having one. end connected to said arm and its otherend engaged with said handle member, said arm and said spring barproviding a continuous constant moment arm' of substantially constantlength, whereby pressure applied to said grip portion is transmitted tothe work through said-11handle member, thence through said springl'b'a'rand iinally through saidwork-engaging member, and -means for indicatingthe amount oi .Dressureapplied to the work by measuring'y the extent ofrelative rock movement between said member and said arm,

said means comprising an operating part extending from said pressureindicating means anda 'second part on the work-engaging membercooperable with the first part to actuate said indicating means.

18. A torque measuring wrench comprising, a head member, a work-engagingmember rockably supported thereby, a spring bar, means iixablyconnecting one end of said spring bar to one of said members, means onthe other of said members pivotally supporting the other end of saidspring bar and-conning it against lateral displacement, and means f-orindicating the pressure applied to the work by registering the extent ofrelative rock movement of said head and s aid work-engaging members. 4

19. A torque measuring wrench adapted for use with means for indicatingthe force applied by the wrench to the work comprising a head memberhavingprovision for operably engaging it with the work, a handle memberrockably connected to said head member, a spring bar carried by one ofsaid members and so mounted that its end portions are retained againstlateral displacement and its mid portion is free to flex, and meansoperably connecting the other of said members to said mid portion sothat the spring member yieldably opposes relative rock movement betweensaid head and handle members.

20. A torque measuring wrench adapted for use with means for indicatingthe force applied by the wrench to the work comprising a head memberhaving provision for operably engaging it with' the work, a handlemember rockably connected to said head member, a spring bar supportedWholly by one of said members, and abutment means carried by the otherof saidmembers and adapted to engage' said spring bar intermediate itsends Vso that pressure applied to said spring bar by one member istransmitted through said spring barv to the work-engaging member and thework.

21. A torque measuring wrench adapted'for use with4 means for indicatingthe force applied 23. A torque measuring wrench comprising a head memberincluding a grip portion, a workengagjng member rockably connectedthereto, an elongated normally straight spring bar having its activeexing part disposed wholly between said rcckable connection and saidgrip portion, means rigidly connecting one end'of said spring bar tosaid work-engaging member, means prolviding va longitudinally slidableconnection between said spring bar and said head member, said connectionconfining said spring bar against movement in either direction relativeto said head member and inv a plane at right angles to the rock axis ofsaid rockably connected members so that said work-engaging member can beutilized to tighten left or right hand threaded work pieces, and meansindicating the amount of pressure applied to the work by measuring theextent of relative rock movement between said head and work-engagingmembers.

24. A torque measuring wrench comprising a head member, a work-engagingmember rotatably mounted in said head member and having a partexteriorly accessible for connection with the work, a rigid arm on saidwork-engaging member and having a longitudinal opening of predeterminedcross-sectional size and length extending from its outer end toward theaxis of rotation of said work-engaging member, an elongated spring barof substantiallyuniform cross section throughout its length having oneend securely mounted in and extending substantially to the rear end ofsaid arm opening, a second l connection between the other end of saidspring members.

by the wrench to the work comprising a head' member having provision foroperably engaging it with the work, a handle member rockably con-Anected to said head member, a spring bar carried wholly by said headmember and having itsoperably connecting said handle member to said midportion so that said spring bar yieldably opfposes relative rockmovement between said head and handle members.

22. A torque measuring wrench adapted for use with means for indicatingthe force applied by the wrench to the work comprising a head memberhaving top and bottom walls, a workengaging member rotatably mounted inthe top and bottom-wallsvof said head member, a spring bar having oneend secured to said work-engaging member, and a connection between theother end of'said spring bar and said head member whereby said springbar opposes relative movement of said members, said connection including,a bar-supporting member having an opening therein in which the end ofsaid spring bar is freely received, said head member having Aalignedopenings in the top and bottom walls thereof with their axes extendingsubstantially parallel withl the axis of rotation of said work-engagingbar and said head member, and means for connecting saidwork-engagingmember with a pressure indicating mechanism responsive to relativemovement of said head and work-engaging 25. A torque measuring wrenchcomprising a head member, a work-engaging member rotatably mounted insaid head member and having a part exteriorly accessible forconnectionwith the work, a rigid arm integrally extending from saidwork-engaging member and having an 'opening of predeterminedcross-sectional size and length in its outer end and extending towardthe axis of rotation of said work-engaging member on a line passingthrough said axis at substantally right langles thereto, an elongated.

straight spring bar of substantially uniform cross section throughouthaving one end-extending into said Varm opening substantially the fulllength of the latter, a connection between the other end of said springbar and said head member, whereby said spring bar yieldably opposesrelative movement between said members, and

members in terms of pressure applied to thel work.

26. A torque measuring wrench comprising an elongated head member havingtop and bottom walls, said head member having aligned circular openingsat the forward end thereof in said tcp and bottom walls, valignedcircular openings at the rear end thereof in said top and bottom wallsand an intermediate opening in said top wall, a work-engaging memberhaving parts rotatably mounted in said forward openings, a spring barconnected at one end to said workengaging member, .a connection` betweenthe other end of said' bar and said head member including a memberhaving parts rotatably mounted in said rear openings, indicatingmechanism displacement 5 permitting free relative longitudinal movementhaving a part tting in said intermediate openlhead member, awork-engaging member rotatably mounted in said head member and having apart exteriorly accessible for connection with the work, a rigidlelement on said work-engaging member and having a longitudinal openingoi' predetermined cross-sectional size and length extending from itsouter end toward the axis oi rotation of said work-engaging member; anelongated spring Abar of substantially uniform cross section throughoutits length having oneA end securely mounted in and extendingsubstantially to the rear end of said elementopening, a secondconnection between the other end 'of said spring bar and said headmember, and means for connecting said work-engaging memb'er vwith apressure indicating mechanism responsive to relative movement of saidhead and work-engaging members.

28. A torque measuring wrench comprising a head member, a work-engagingmember rotatably mounted with respect to said head member and having aportion provided with an opening, said opening extending in adirectionftransverse to the axis of rotation of saidwork-engagingmemner'and lying across said axis, an elongated flexiblespring barvhaving one end thereof securelyv mounted in said opening andhavingvits opposite end connected to said headmember for yieldablyopposing relative rotary' movement of said head member and work-engagingmember,

and indicating means operable by said work-engaging member as sad headmember and workengaging member rotate relative to each other forindicating the force applied to the work through said members and springbar,

29. A torque wrench comprising a body member, a head member rotatablycarried by said body member, a torqueresisting beam carried at one endby one of said members, means providing a pivotal connection between theother end of said beam-and the other of said members, indicating means,andfmeans for connecting one .f end portion of said beam with saidindicating means.

30. A torque. measuring lwrench adapted to tighten work having right orleft hand threads comprising, a headmember, a work-engaging memberrockably supported thereby, a sp g bar, meansnxably connecting lone endof s d spring bar to one of said members, means on the other of saidmembers slidably receiving the other end of said spring bar andconilning it against lateral displacement in opposite directions, andmeans for indicating the pressure applied'to the work by registering theextent of relative rock'movement of said head and said work-engagingmembers;

.31. A w'renchadapted to tighten work having rightor left hand threadscomprising, a head member, a work-engaging member rockably supportedthereby, a spring bar, means iixably connectingone end portion of saidspring bar to one of said members, abutment means on the other of saidAmembers engaging the other end portion and conilning it against lat--oi' said spring bar d d in opposite directions. while plied to the workby registering the extent of relative rock'movement of said head andsaidv I work-engaging members. n

32. 'A torque measuring wrench comprising, a handle member, awork-engagingmember rockably supported thereby, an arm Vextendingsubstantially radially from said work-engaging member, a spring bar,means xably connecting one end of said spring bar to said arm, means onsaid handle memberpivotally supporting the other end of said sprlngbarand conningit against lateral displacement, and means forindicating thepressure applied to the work by registering the extent of relative rockmovement of said head and said work-engaging members. i Y

33. A' torque measuring wrench comprising, a handle member, awork-engaging member pivotally supported adjacent one en d of saidhandle member, a normally straight spring bar yield- .ably opposingrelative rock movement of saidwork-engaging member and said handlemember, said spring bar having one end thereof flxedly mounted in saidwork-engaging member and extendingv across the axis of rotation of saidwork-engaging member and having its opposite end arranged to havea forceapplied thereto through said handle member, and means responsive toexing of said spring bar and consequent relative rock movement of saidwork-engaging and handle members for indicating the force applied to thework.

34. A torque measuring wrench comprising, a

handle member, a work-engaging member pivotally supported adjacent oneend of said handle member, a normally straight spring bar yieldablyopposing relative rock movement of said work-engaging member and saidhandle member, 'said spring bar having one end` thereof fixcd1)1 mountedin said work-engaging member and extending across the axis of rotationof said work-engaging member and having its opposite end pivotallyconnected with said handle member, and means responsive to exing of saidspring bar and consequent relative rock. movement of said work-engagingand handle members for indicating the force applied to the work.

35. A torque measuring wrench comprising, a handle member having a gripportion on one end thereof, a work-engaging member rockably supportedbythe other end of said handle member, a rigid work-engaging elementrigidly connected to said work-engaging member to maintain a constantrelationship between the axis of rotation of the work. and the axis ofrotation of said handle member relative to said work-engaging member, anormally straight spring bar member rigidly connected at oneend to saidwork-engagl ing member and extending toward said grip portion so thatits entire active flexing portion is disposed wholly between the -axisof rotation of said work-engaging member and said grip por- I.

, tionin general longitudinal alignment with said work-engaging memberand said grip portion, means operably connecting the other end of saidspring bar member to said handle member so ber is maintained constant,indicating means v that pressure is applied to the` lwori: directlythrough said handle member, spring bar member, work-engaging member and,work-engaging element in the order named, whereby the leverage betweenthe work and said spring bar memtlereof, and means -for indicating theforce apof said indicating means to one of the other of said memberswhereby it is actuated to indicate one end of said handle, means coaxialwith the i axis of said pivotally supported'portion by which saidwork-engaging member may be connected with the work, an arm member onsaid workengaging member and extending longitudinally of said handlemember, a normally straight, stiff spring bar extending from said armlongitudinally of said handle. member in substantially radial relationto the axis of rotation of VVthe pivoted portion of said work-engagingmember and having one end connected to said arm and its other endengaged with said handle member at a -predetermined distance from theaxis of rotation of the pivoted portion of said work-engaging member andat a point between` said grip portion and `said axis, said arm and saidspring bar providing a continuous constant moment arm of substantiallyconstant length, whereby pressure applied to said grip portion istransmitted to the work through said handle member, thence through thespring bar and finally through saidpivoted portion of said work-engagingmember.

37. A torque measuring wrench adapted for use with means for indicatingthe force applied to the work which comprises, a handle member extendingsubstantially throughout the length of the wrench and having a gripportion adjacent one end thereof, .a work-engaging member hav- -ing aportion pivotally supported adjacent the other end of said handle memberand another portion located on the axis of the first portion and adaptedfor connection of the work-engaging member with the work', a normallystraight spring bar disposed in endto end relation to said grip portionand the pivoted portion of said work-engaging member with itslongitudinal axis extending substantially radially relative to the axisof the pivoted portion of said workengaging member, said spring barhaving one end iixedly mounted in said work-engaging membersubstantially at the pivotal axis thereof with its other end in slidableengagement with said handle member at a point between said axis of thepivoted portion of said work-engaging member and said grip portion andat a predetermined and substantially constant distance from the axis ofthe pivoted portion of said Work-engaging member, whereby pressureapplied to said grip portion is transmitted directly through said handlemember, thence forwardly through said spring bar from one end thereof tothe other, thence to the pivoted portion of said work-engaging memberand to the work, through a constant moment arm effective to rotate thework notwithstanding the position at which pressure is applied to saidgrip portion.

38. A torque wrench comprising: a handle member including an elongatedbody member having a chamber extending throughout substantially the fulllength of the body member and a longitudinally extending grip portioncarried by said body member; an indicator carried by said handle member,said indicator being located at a point between the ends of saidchamber; a work-engaging member having an enlarged portion in saidchamber and a relatively smaller portion extending from said enlargedportion to the exterior of said chamber and adapted to be operativelyconnected with the work; means connecting said enlarged portion of saidWork-engaging member to said handle member, whereby force applied tosaid handle member is transmitted to said work-engaging member throughsaid connecting means, the

enlarged portion of said work-engaging mem-A ber being arranged so thatit can turn relative to said handle member in proportion to the forceapplied to the work; an elongated arm means in said chamber, one end ofsaid elongated arm means being xedly secured to the enlarged portion ofsaid work-engaging member and extending radially from said enlargedportion and lengthwise of said chamber toward said grip portion, theopposite end of said elon- 'l gated arm means being free to move uponturning of said enlarged portion of said work-engaging member relativetosaid handle member: and means operatively connecting said free end ofsaid elongated arm means to said indicator to actuate said indicatorupon movement of said free end of said elongated arm means.

HERMAN W. ZUWMERMAN.

